Directed Gas Stream Reduces Tractor Aerodynamic Drag
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional tractor-trailer combinations experience excessive aerodynamic drag due to bluff body characteristics, particularly the abrupt transition at the leading edge of the tractor hood, leading to airflow separation and increased pressure losses.
Innovation Solution
A directed gas generation unit is integrated into the vehicle to generate and direct a pressurized gas stream forwardly and at an acute angle to the longitudinal axis, reducing drag by counteracting airflow separation and turbulence.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Force
If the front section is streamlined to reduce abrupt changes in air flow, then pressure drag is reduced, but the design becomes more complex and may still have discontinuous regions causing wake formation
Solution Approach 1:
The patent uses a gas generation unit that directs a stream of gas (pneumatic) toward the front section of the vehicle to counteract airflow separation and reduce pressure drag, rather than relying solely on complex geometric streamlining of the hood structure
Solution Approach 2:
The invention changes the physical state and direction of the air flow by introducing a directed gas stream that modifies the flow characteristics over the front section, transforming the flow from separative to attached state to reduce drag
2Force
If fixed air deflectors are mounted on the roofs of tractor cabs to reduce aerodynamic drag, then drag forces are reduced, but the device complexity and manufacturing cost increase
Solution Approach 1:
Instead of using solid air deflectors mounted on the tractor cab, the patent employs a gas generation unit that emits a directed stream of gas to achieve the same aerodynamic effect, simplifying the mechanical structure and reducing manufacturing complexity
Solution Approach 2:
The invention replaces the mechanical air deflector system with a pneumatic gas stream system, substituting solid structural components with a fluid-based approach that achieves drag reduction without complex mechanical installations
3Force
If the hood is made to slope downwardly from the windshield toward the front to reduce flow separation, then pressure drag is reduced, but discontinuous regions for under hood components create wake formation
Solution Approach 1:
The directed gas stream from the gas generation unit provides a continuous flow that covers discontinuities in the hood design, maintaining airflow attachment over the front section even when packaging requirements create discontinuous regions for radiators and air ducting
Solution Approach 2:
The gas stream is directed in advance toward the front section to counteract potential flow separation before it occurs, preventing wake formation and maintaining airflow continuity despite discontinuities in the vehicle structure
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The system effectively reduces aerodynamic drag by minimizing airflow separation and turbulence, thereby enhancing the fuel efficiency and reducing operating costs of tractor-trailer combinations.
Implementation Method 1
The directed gas generation unit is capable of generating a quantity of pressurized gas and directing the quantity of pressurized gas forwardly of the front section and outwardly of the vehicle
Data Source
AI summary
Systems and methods are disclosed that utilize exhausted gases from an internal combustion engine (e.g., piston engine, rotary engine, turbine engine, etc.) of a vehicle for reducing the aerodynamic drag thereon. In some disclosed examples, the systems and methods utilize a generated gas flow from, for example, electric fans, engine driven or pneumatically/hydraulically driven pumps, etc., for reducing aerodynamic drag. The generated gas flows in several disclosed examples are directed in a generally opposing direction of (i.e., against) prevailing cross winds.